WO2022254710A1

WO2022254710A1 - Communication device, communication system, communication method, and communication program

Info

Publication number: WO2022254710A1
Application number: PCT/JP2021/021418
Authority: WO
Inventors: 豪矢沢; 尊広久保; 夏樹安原; 慎一吉原
Original assignee: 日本電信電話株式会社
Priority date: 2021-06-04
Filing date: 2021-06-04
Publication date: 2022-12-08
Also published as: JPWO2022254710A1

Abstract

An information processing device according to an embodiment of the present invention is a communication device that is connected to a user device via an access port and that transmits, via a network, user data from the user device to another user device which is connected to another communication device. The information processing device comprises an acquisition function unit and an announcement function unit. Upon receipt of a request for acquiring an MAC address of a user device that is newly connected to the access port, the acquisition function unit acquires the MAC address of the newly connected user device. The announcement function unit announces, to another communication device, the MAC address acquired by the acquisition function unit.

Description

Communication device, communication system, communication method and communication program

Embodiments of the present invention relate to communication devices, communication systems, communication methods, and communication programs.

　There are a certain number of users who want network services with short communication interruption times associated with redundancy switching. As a technique for providing a network service with a short communication interruption time, for example, Non-Patent Document 1 discloses a non-instantaneous interruption redundancy switching technique. Ethernet (registered trademark) is generally used for the network.

In the technology disclosed in Non-Patent Document 1, in a one-to-one transmission/reception configuration, a device that performs non-instantaneous interruption processing (hereinafter referred to as a non-instantaneous interruption device) located at a transmission source site Duplicates the user data frame to be transmitted given from the user terminal at the site. This duplicated frame is transferred from the uninterrupted device through two different routes of the relay network, and reaches the uninterrupted device located at the destination site. The uninterrupted device at the destination site selects one of the identical frames arriving from the two routes and transfers it to the user terminal at the destination site.

In order to manage how far frames have been transmitted and received in each relay network, the uninterruptible device at the source gives a sequence number to the frames to be duplicated as traffic flow management information. The destination hitless device holds the sequence number of the next frame to be processed in the form of an expected number. When a frame with a number different from the expected number arrives, the destination uninterruptible device waits until the frame with the expected number arrives. As a result, communication without jumps in the order of frames can be realized.

In addition to the one-to-one sending/receiving configuration, one-to-n (n≧2) configuration, that is, communication between multiple locations where there are multiple receiving sides, the route is similarly made redundant for high reliability, and failures can occur. For example, a network service that switches paths without instantaneous interruption by an uninterrupted device is required. In inter-site communication, it is necessary to classify user data frames for each pair of transmitting and receiving devices, assign a sequence number to each pair, and select user data frames by uninterrupted devices on the transmitting and receiving sides. be. A logical classification unit by this pair of transmitting and receiving devices is defined as a traffic flow.

For example, in uninterrupted equipment A, a user data frame addressed to user terminal B connected from user terminal A to uninterrupted equipment B and a user data frame addressed to user terminal C connected to uninterrupted equipment C , the uninterruptible device A associates the pair of uninterrupted devices as one traffic flow, assigns a sequence number to each, and transmits it to the network. In a network using Ethernet, a frame destined for user terminal B is received only by uninterruptible device B, and a frame destined for user terminal C is received by a network switch arranged in the network through MAC address learning in the network switch. It is designed to be received only by the hitless device C.

In this case, it is necessary for the uninterrupted device on the transmission side to determine the destination uninterrupted device from the MAC address of the destination user terminal and classify the traffic flow. Therefore, the uninterruptible device on the transmission side needs to associate and learn the MAC address of the user terminal of the transmission destination and the uninterrupted device of the transmission destination.

As a method for this learning, for example, the MAC address exchange method used for EVPN (Ethernet VPN) as disclosed in Non-Patent Document 2 is utilized, and the MAC address of the destination user terminal is can be exchanged between EVPN is a technology that implements Ethernet VPN (L2) in an IP (L3) network. In EVPN, when a PE (Provider Edge) receives a signal from a local CE (Customer Edge), it learns the MAC address and sends MAC/IP to other PEs in the form of Route Type 2 (MAC/IP Advertisement Route) Advertise your Route. Then, the PE that has received this MAC/IP Route learns the MAC addresses of the CEs connected to PEs other than itself based on it.

In EVPN, the PE advertises its MAC address upon signal transmission from the local CE. Therefore, at the timing when another PE tries to start communication, if the local CE of the PE has not transmitted a signal, that is, if the MAC address has not been advertised, the MAC address is transmitted to the other PE. It has not been learned and communication cannot be started.

Therefore, in a network that shares MAC addresses between nodes, not only in uninterrupted redundancy switching technology and EVPN between multiple bases, at the time when communication between nodes is to be started, the source node is surely A technique is needed to ensure that MAC address learning is complete for destination nodes.

This invention seeks to provide a technology that enables MAC address learning to be performed at an appropriate time.

In order to solve the above problems, a communication device according to one aspect of the present invention is connected to a user device via an access port, and transmits user data from the user device to another user device connected to another communication device. A communication device for transmitting over a network, comprising an acquisition function and an advertisement function. The acquisition function unit acquires the MAC address of the newly connected user device upon receiving a request to acquire the MAC address of the user device newly connected to the access port. The advertisement function unit advertises the MAC address acquired by the acquisition function unit to other communication devices.

According to one aspect of the present invention, when a request to acquire the MAC address of a user device newly connected to an access port is received, the communication device advertises the MAC address of the user device, communication device to perform MAC address learning. Therefore, it is possible to provide a technique that enables MAC address learning to be performed at an appropriate time.

FIG. 1 is a schematic diagram showing a communication system to which a communication device according to a first embodiment of the invention is applied. FIG. 2 is a diagram showing an example of the hardware configuration of a computer when the communication device according to the first embodiment is configured by a computer. 3 is a block diagram illustrating an example of the functional configuration of the communication device according to the first embodiment; FIG. 4 is a flowchart illustrating an example of the operation of the communication device according to the first embodiment; FIG. FIG. 5 is a schematic diagram showing a communication system to which the communication device according to the second embodiment of the invention is applied. FIG. 6 is a block diagram showing an example of the configuration of a communication device according to the second embodiment. FIG. 7 is a flow chart showing an example of the operation of the communication device according to the second embodiment. FIG. 8 is a block diagram showing an example of the configuration of a communication device according to the third embodiment of the invention. FIG. 9 is a flowchart showing an example of the operation of the communication device according to the third embodiment when the communication device is the MAC address inquiry source. FIG. 10 is a flowchart showing an example of the operation of the communication device according to the third embodiment when the communication device is the MAC address inquiry destination. FIG. 11 is a block diagram showing an example of configuration of a communication device according to the fourth embodiment of the present invention. FIG. 12 is a flowchart showing an example of the operation of the communication device according to the fourth embodiment when the communication device is the MAC address inquiry destination. FIG. 13 is a block diagram showing an example of configuration of a communication device according to the fifth embodiment of the present invention. FIG. 14 is a schematic diagram for explaining an EVPN communication system. FIG. 15 is a schematic diagram for explaining a hitless redundancy switching communication system. FIG. 16 is a schematic diagram for explaining an uninterrupted redundant switching communication system that supports multiple bases. FIG. 17 is a block diagram showing an example of the configuration of a communication device for application as a hitless device in a hitless redundancy switching communication system.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.

[First embodiment]
(Constitution)
FIG. 1 is a schematic diagram showing a communication system to which a communication device according to a first embodiment of the invention is applied.
The communication system includes first to third communication devices CA1, CA2, CA3 interconnected via a network NW. Hereinafter, the first to third communication devices CA1, CA2, and CA3 will be referred to as communication device CA when there is no particular need to distinguish between them. A communication device CA is a communication device according to the first embodiment. Note that the communication device may function as a transmitting device in a communication system or may function as a receiving device.

A first user device UA1 is connected to the first communication device CA1, a second user device UA2 is connected to the second communication device CA2, and a third user device UA3 is connected to the third communication device CA3. Hereinafter, the first to third user apparatuses UA1, UA2, and UA3 will be referred to as user apparatuses UA when there is no particular need to distinguish them.

FIG. 2 is a diagram showing an example of the hardware configuration of a computer when the communication device CA according to the first embodiment is configured by a computer. The communication device CA has a hardware processor 1 such as a CPU (Central Processing Unit). In communication device CA, program memory 2 , data memory 3 , first communication interface 4 , and second communication interface 5 are connected to processor 1 via bus 6 . By using a multi-core and multi-threaded CPU, it is possible to execute a plurality of information processes at the same time. Also, the processor 1 may include a plurality of CPUs.

The program memory 2 is a non-temporary tangible computer-readable storage medium, for example, a non-volatile memory such as a HDD (Hard Disk Drive) or SSD (Solid State Drive) that can be written and read at any time, and a non-volatile memory such as a ROM. It is used in combination with a static memory. The program memory 2 stores a communication program necessary for the processor 1 to execute various control processes according to this embodiment.

The data memory 3 is used as a tangible computer-readable storage medium, for example, by combining the above nonvolatile memory and a volatile memory such as RAM (Random Access Memory). This data memory 3 is used to store various data obtained and created in the process of performing various processes. That is, in the data memory 3, an area for storing various data is appropriately secured in the process of performing various processes.

The first communication interface 4 includes an access port to which the user equipment UA can be connected, and transmits/receives control signals and user data to/from the user equipment UA.

The second communication interface 5 includes a WAN (Wide Area Network) port for connecting to the network NW, and a communication module according to the communication medium, communication method, and communication protocol of the network NW. to transmit control signals and user data to and from another communication device CA.

FIG. 3 is a block diagram showing an example of the functional configuration of the communication device CA according to the first embodiment. Note that FIG. 3 shows only functional units related to transmission of user data from the user device UA. That is, since the functional unit related to reception of user data transmitted from another communication device CA via the network NW is the same as that of the conventional communication device, illustration and description thereof will be omitted.

As shown in FIG. 3, the communication device CA includes an access port 11, a WAN port 12, a link-up detection function unit 13, a MAC address acquisition function unit 14, an address database (address DB in FIG. 3) 15, a MAC address It has an advertisement function unit 16 , a MAC address advertisement reception function unit 17 and a header addition function unit 18 . In FIG. 3, solid-line arrows indicate the flow of control signals between functional units, and broken-line arrows indicate the flow of user data to be transmitted.

The access port 11 is a port of the first communication interface 4 for exchanging control signals and user data with the user device UA. The WAN port 12 is a port of the second communication interface 5 for exchanging control signals and user data with another communication device CA via the network NW.

The link-up detection function unit 13 receives a link state signal SG1 indicating the link state of the access port 11, and according to this link state signal SG1, the user device UA is newly connected to the access port 11 and becomes ready for communication. Detect link up. At the linkup timing, the linkup detection function unit 13 transmits an acquisition request signal SG2 requesting acquisition of the MAC address to the MAC address acquisition function unit 14 .

Upon receiving the acquisition request signal SG2, the MAC address acquisition function unit 14 obtains the MAC address from the user apparatus UA via the access port 11 and requests it to acquire and reply to the MAC address. Sends a response request signal SG3. Then, the MAC address acquisition function unit 14 receives a MAC address reply signal SG4 indicating the MAC address of the user device UA returned from the user device UA via the access port 11 . For example, the MAC address acquisition function unit 14 can transmit ARP (Address Resolution Protocol) to the user apparatus UA and read the transmission source MAC address in the loopback signal from the user apparatus UA. Thus, the MAC address acquisition function unit 14 can acquire the MAC address of the user device UA. The MAC address acquisition function unit 14 transmits the acquired MAC address to the address database 15 by means of a MAC address notification signal SG5, and transmits a MAC address acquisition completion notification signal SG6 indicating completion of acquisition of the MAC address to the MAC address advertisement function unit 16. Send to

The address database 15 is a MAC address database that accumulates acquired MAC addresses indicated by the MAC address notification signal SG5 transmitted from the MAC address acquisition function unit 14 . Also, the address database 15 pairs a device ID, which is information for identifying another communication device CA connectable via the network NW, with the MAC address of the user device UA connected to the communication device CA. are accumulating.

Upon receiving the MAC address acquisition completion notification signal SG6 from the MAC address acquisition function unit 14, the MAC address advertisement function unit 16 transmits a MAC address read request signal SG7 requesting the address database 15 to read the MAC address. The address database 15 returns a MAC address notification signal SG8 indicating the stored MAC address to the MAC address advertisement function unit 16 in response to the MAC address readout request signal SG7. Thus, the MAC address advertisement function unit 16 can read the MAC address from the address database 15. FIG. The MAC address advertising function unit 16 then transmits to the WAN port 12 a MAC address advertising signal SG9 indicating the read MAC address and the device ID of the communication device CA. Thereby, the MAC address advertising function unit 16 can advertise the MAC address of the user device UA connected to the communication device CA to another communication device CA via the WAN port 12 .

When the WAN port 12 receives the MAC address advertised by another communication device CA, the WAN port 12 sends a MAC address advertisement information signal SG10 indicating the received MAC address and the device ID of the communication device CA to the MAC address advertisement reception function unit 17. Send to The MAC address advertisement reception function unit 17 pairs the device ID and MAC address of the other communication device CA included in the MAC address advertisement information signal SG10, and transmits them to the address database 15 by the MAC address advertisement information notification signal SG11. do. The address database 15 pairs and accumulates the device ID and the MAC address indicated by the MAC address advertisement information notification signal SG11. In this way, the MAC address advertisement reception function unit 17 acquires a pair of the device ID of another communication device CA and the MAC address of the user device UA connected thereto, and registers it in the address database 15, that is, the MAC address can learn.

The header adding function unit 18 receives user data, eg, user data frames, from the user device UA via the access port 11 . A user data frame includes a header and a data payload. The header addition function unit 18 acquires destination information from the header of the user data frame. The destination information is, for example, the MAC address of the destination user device UA. Then, the header addition function unit 18 transmits to the address database 15 a header information read request signal SG12 including the MAC address of the destination user apparatus UA. The address database 15 returns a pair of the MAC address corresponding to the MAC address included in the header information read request signal SG12 and the device ID of the communication device CA to the header addition function unit 18 as a header information notification signal SG13. The header adding function unit 18 creates header information for the user data frame to be transmitted based on the device ID of the communication device CA indicated by this header information notification signal SG13, and adds it to the user data frame. Then, the header adding function unit 18 transfers the user data frame to which the header information is added to the WAN port 12, and unicasts it from the WAN port 12, thereby transmitting it to the communication device CA corresponding to the destination user device UA. .

The link-up detection function unit 13, the MAC address acquisition function unit 14, the MAC address advertisement function unit 16, the MAC address advertisement reception function unit 17, and the header addition function unit 18 all use the communication program stored in the program memory 2 as a processor. 1 is read and executed. Some or all of these processing functions may be implemented in various other forms, including integrated circuits such as Application Specific Integrated Circuits (ASICs) or field-programmable gate arrays (FPGAs). May be. The address database 15 can also be configured in the data memory 3 .

(motion)
Next, operation of the communication device CA according to the first embodiment will be described.
FIG. 4 is a flow chart showing an example of the operation of the communication device CA according to the first embodiment. When the communication device CA is constructed by a computer as shown in FIG. 2, the program memory 2 stores a communication program necessary for executing the control processing shown in this flow chart, and the processor 1 executes the communication. By executing the program, each functional unit of the communication device CA as shown in FIG. 3 can be operated.

The processor 1 functions as the link-up detection function unit 13 and detects, based on the link state signal SG1 from the access port 11 in the first communication interface 4, whether or not the link-up to which the new user equipment UA is connected is detected. It judges (step S11).

If it is determined that a linkup has been detected (YES in step S11), the processor 1 executes processing operations as the MAC address acquisition function unit 14. That is, the processor 1 transmits a MAC address reply request from the access port 11 of the first communication interface 4 to the linked-up user apparatus UA (step S12). Then, the processor 1 determines whether or not a reply from the user device UA is received through the access port 11 (step S13). If it is determined that no response has been received from the user device UA (NO in step S13), the processor 1 executes the processing operation of step S13 again. The processor 1 thus waits to receive a reply from the user equipment UA.

Then, when determining that a reply from the user device UA has been received (YES in step S13), the processor 1 pairs the received MAC address of the user device UA with the device ID of the communication device CA, and stores the MAC address in the address database 15. It is stored (step S14).

After that, the processor 1 functions as the MAC address advertising function unit 16 and reads out the MAC address paired with the device ID from the address database 15 (step S15). The processor 1 then advertises the read MAC address and device ID on the network NW from the WAN port 12 of the second communication interface 5 (step S16). Thereby, the processor 1 can transmit the MAC address of the user apparatus UA newly connected to the communication apparatus CA to the other communication apparatus CA. After that, the processor 1 shifts to the processing operation of step S11.

Further, when it is determined in step S11 that no link-up has been detected (NO in step S11), the processor 1 performs the processing operation as the MAC address advertisement reception function unit 17. That is, the processor 1 determines whether or not the MAC address advertised by the other communication apparatus CA is received from the MAC address advertisement information signal SG10 from the WAN port 12 in the second communication interface 5 (step S17). When determining that the MAC address advertised by another communication device CA has been received (YES in step S17), the processor 1 pairs the received MAC address with the device ID advertised together with the MAC address to generate an address. It is stored in the database 15 (step S18). In this way, when a new user device UA is connected to another communication device CA, that is, when the user device UA is newly installed, the processor 1 sets the device ID of the communication device CA and the newly connected user device. UA's MAC address can be learned. After that, the processor 1 shifts to the processing operation of step S11.

If it is determined in step S17 that the MAC address advertised by the other communication device CA has not been received (NO in step S17), the processor 1 performs the processing operation as the header addition function unit 18. That is, the processor 1 determines whether or not the access port 11 of the first communication interface 4 has received a user data frame from the user device UA (step S19). When determining that the user data frame has not been received (NO in step S19), the processor 1 proceeds to the processing operation of step S11.

On the other hand, if it is determined that the user data frame has been received (YES in step S19), the processor 1 acquires the MAC address of the destination user device UA, which is the destination information, from the user data frame, Header information corresponding to the address is read from the address database 15 (step S20). This read header information is a pair of the MAC address and the device ID of the communication device CA. The processor 1 adds this read header information to the user data frame (step S21). Then, the processor 1 unicasts the user data frame to which this header information is attached from the WAN port 12 of the second communication interface 5, thereby transmitting it to the communication device CA corresponding to the destination user device UA ( step S22). After that, the processor 1 shifts to the processing operation of step S11.

The processing operation related to the reception of user data transmitted from another communication device CA via the network NW is the same as that of a conventional communication device, so illustration and description thereof will be omitted.

In the first embodiment as described above, for example, when the third user device UA3 is newly installed in the third communication device CA3, the third communication device CA3 detects link-up of the third user device UA3. , requests the third user apparatus UA3 to return the MAC address. Then, the third communication device CA3 acquires the MAC address from the response from the third user device UA3 and advertises it to other communication devices CA. This allows the first and second communication devices CA1 and CA2 to learn the MAC address of the third user device UA3 newly installed in the third communication device CA3.

As described above, the communication device CA according to the first embodiment is connected to the user device UA via the access port 11, and transmits user data from the user device UA to another user device connected to another communication device CA. A communication device that transmits to a UA via a network NW, and receives a request to acquire the MAC address of the user device UA newly connected to the access port 11, and obtains the MAC address of the newly connected user device UA. a MAC address acquisition function unit 14 as an acquisition function unit that acquires a MAC address advertisement function unit 16 as an advertisement function unit that advertises the MAC address acquired by the MAC address acquisition function unit 14 to other communication devices CA; Prepare. In this way, upon receiving a request to acquire the MAC address of the user apparatus UA newly connected to the access port 11, the communication apparatus CA advertises the MAC address of the user apparatus UA, The communication device CA is made to perform MAC address learning. Therefore, the other communication device CA can learn the MAC address of the newly installed user device UA before the MAC address is required, that is, at an appropriate time.

Note that the communication device CA detects the link-up of the access port 11, and when the access port 11 is linked-up, an acquisition request signal as a request to acquire the MAC address of the newly connected user device UA. A link-up detection function unit 13 that transmits SG2 to the MAC address acquisition function unit 14 is further provided. In this way, the communication device CA can actively acquire the MAC address when the user device UA is newly installed, and advertise it to other communication devices CA. Therefore, the other communication device CA can learn the MAC address of the newly installed user device UA before the MAC address is required, that is, at an appropriate time.

[Second embodiment]
Next, a second embodiment of the invention will be described. In the description of the second embodiment, the same reference numerals as those used in the description of the first embodiment are given to the same configurations and processing operations as those of the first embodiment, and the description thereof will be omitted. shall be

(Constitution)
FIG. 5 is a schematic diagram showing a communication system to which the communication device according to the second embodiment of the invention is applied. In this communication system, a second user apparatus UA2 and a fourth user apparatus UA4 are connected to a second communication apparatus CA2 via a switch SW.

In the first embodiment described above, the communication device CA determines whether or not to newly install the user device UA when the access port 11 is linked up. However, when the communication device CA and the user device UA are connected via the switch SW, the access port 11 is always linked up with the switch SW regardless of the presence or absence of the user device UA. Therefore, the communication device CA cannot determine whether the user device UA is newly installed.

FIG. 6 is a block diagram showing an example of the configuration of the communication device CA according to the second embodiment, which handles such cases. The communication device CA has a timer function unit 19 as shown in FIG. 6 instead of the link-up detection function unit 13 in the first embodiment.

The timer function unit 19 counts a predetermined period of time, and every time the period of time elapses, the timer function unit 19 transmits a timing notification signal SG14 indicating that it is time to acquire the MAC address to the MAC address acquisition function unit 14. . The fixed period of time is a period of time set for periodically trying to acquire the MAC address of the newly installed user equipment UA.

In response to the reception of this timing notification signal SG14, the MAC address acquisition function unit 14 sends a MAC address response request to the user device UA via the access port 11 to acquire the MAC address and make a response. Send signal SG3. Then, the MAC address acquisition function unit 14 receives a MAC address reply signal SG4 indicating the MAC address of the user device UA returned from the user device UA via the access port 11 . For example, the MAC address acquisition function unit 14 can transmit Ether OAM (Ether-LT (LinkTrace)) to the user apparatus UA and read the transmission source MAC address in the loopback signal from the user apparatus UA. Thus, the MAC address acquisition function unit 14 can acquire the MAC address of the user device UA.

(motion)
Next, operation of the communication device CA according to the second embodiment will be described.
FIG. 7 is a flow chart showing an example of the operation of the communication device CA according to the second embodiment.

In the second embodiment, the processor 1 determines whether or not it is time to periodically acquire the MAC address clocked by the timer function unit 19 (step S31). If it is determined that it is not time to acquire the MAC address (NO in step S31), the processor 1 proceeds to the processing operation of step S17, and determines whether or not the MAC address advertised by another communication device CA has been received. A decision will be made as to whether

On the other hand, if it is determined that it is time to acquire the MAC address (YES in step S31), the processor 1 transmits a MAC address reply request from the access port 11 of the first communication interface 4 (step S12). . In this case, in this embodiment, polling is used to transmit a MAC address response request to the user apparatus UA via the switch SW. Then, the processor 1 shifts to the processing operation of step S13 and waits for receiving a reply from the newly installed user device UA.

In the second embodiment as described above, for example, the second communication device CA2 periodically polls to request the MAC address from the user device UA. Then, the second communication device CA2 acquires the MAC address from a response from, for example, the newly installed fourth user device UA4, and advertises it to other communication devices CA. This allows the first and third communication devices CA1 and CA3 to learn the MAC address of the fourth user device UA4 newly installed with respect to the second communication device CA2.

As described above, the communication device CA according to the second embodiment measures time, and sends the timing notification signal SG14 as a request to acquire the MAC address of the newly connected user device UA every time a certain period of time elapses. A timer function unit 19 is provided for sending to the MAC address acquisition function unit 14 . In this way, the communication device CA actively acquires the MAC address of the newly installed user device UA by periodically polling for the presence or absence of the newly installed user device UA, and sends it to another communication device CA. It can advertise, that is, periodically transmit a MAC address reply request from the access port 11 . Therefore, the other communication device CA can learn the MAC address of the newly installed user device UA before the MAC address is required, that is, at an appropriate time.

[Third Embodiment]
Next, a third embodiment of the invention will be described. In the description of the third embodiment, the same reference numerals as those used in the description of the first embodiment are given to the same configurations and processing operations as those of the first embodiment, and the description thereof will be omitted. shall be

(Constitution)
A communication system to which the communication apparatus according to the third embodiment of the present invention is applied is, for example, the communication system described in the second embodiment shown in FIG.

FIG. 8 is a block diagram showing an example of the configuration of a communication device CA according to the third embodiment of the invention. The communication device CA has a timer function unit 19, a MAC address identification function unit 20, a buffer function unit 21, and a discard function unit 22, as shown in FIG. 6, instead of the linkup detection function unit 13 in the first embodiment. is doing.

The MAC address identification function unit 20 receives user data frames from the user device UA received via the access port 11 . Then, the MAC address identification function unit 20 extracts the destination MAC address from the user data frame, and transmits to the address database 15 a MAC address read request signal SG15 requesting reading of the MAC address corresponding to the destination MAC address. . The address database 15 returns a MAC address notification signal SG16 indicating the stored MAC address to the MAC address identification function unit 20 in response to the MAC address readout request signal SG15. Based on this MAC address notification signal SG16, the MAC address identification function unit 20 can determine whether the destination MAC address has been learned in the address database 15 or not. When determining that the destination MAC address has been learned, the MAC address identification function unit 20 transmits the received user data frame to the header addition function unit 18 . On the other hand, when determining that the destination MAC address has not been learned, the MAC address identification function unit 20 transmits the received user data frame to the buffer function unit 21 .

Upon receiving a user data frame, the buffer function unit 21 buffers it. For example, it is stored in a temporary storage area provided in the data memory 3 . Then, the buffer function unit 21 extracts the destination MAC address from the user data frame, and sends an inquiry request signal SG17 for inquiring whether or not the user apparatus UA is newly installed and a MAC address notification signal SG18 indicating the destination MAC address to the MAC address. It is transmitted to the address advertisement reception function unit 17 . Further, when the MAC address identification function unit 20 receives from the MAC address advertisement reception function unit 17 an inquiry result signal SG19 indicating that a new user apparatus UA is installed, the MAC address identification function unit 20 sends the buffered user data frame to the header addition function unit 18 .

At the same time as sending the inquiry request signal SG17, the buffer function unit 21 also sends a count start request signal SG20 requesting the timer function unit 19 to start counting. The timer function unit 19 starts time counting from the reception of the count start request signal SG20, and when it counts a predetermined waiting time, it returns a count end notification signal SG21 to the buffer function unit 21. do. If the buffer function unit 21 has not yet received the inquiry result signal SG19 from the MAC address advertisement reception function unit 17 at the timing of receiving this count end notification signal SG21, the buffer function unit 21 sends the buffered user data frame to the discard function unit 22. Send. The discard function unit 22 discards the received user data frame.

The MAC address advertisement reception function unit 17 transmits a MAC address advertisement request signal SG22 requesting advertisement of a new MAC address to the WAN port 12 in response to the inquiry request signal SG17 from the buffer function unit 21. As a result, the MAC address advertisement reception function unit 17 can request other communication devices CA via the WAN port 12 to advertise the MAC address of the user device UA newly installed in those communication devices CA.

Further, in this embodiment, when the WAN port 12 receives a request for MAC address advertisement transmitted by another communication device CA, the WAN port 12 sends a MAC address advertisement request signal SG23 indicating that such a request has been received. Send to the acquisition function unit 14 . In response to receiving the MAC address advertisement request signal SG23, the MAC address acquisition function unit 14 acquires the MAC address for the user device UA via the access port 11 as described in the second embodiment. MAC address response request signal SG3 requesting a response. Then, the MAC address acquisition function unit 14 receives a MAC address reply signal SG4 indicating the MAC address of the user device UA returned from the user device UA via the access port 11 .

The MAC address acquisition function unit 14, address database 15, and MAC address advertisement function unit 16 operate as described in the first embodiment. As a result, the MAC address advertisement function unit 16 transmits the MAC address advertisement signal SG9 to the WAN port 12, and transmits it to another communication device CA via the WAN port 12 of the user device UA newly installed in the communication device CA. A new MAC address can be advertised.

The MAC address advertisement reception function unit 17 receives from the WAN port 12 the MAC address advertisement information signal SG10 indicating the new MAC address advertised by the other communication device CA. The MAC address advertisement reception function unit 17 determines whether the MAC address included in this MAC address advertisement information signal SG10 matches the MAC address being queried. If they match, the MAC address advertisement reception function unit 17 transmits to the buffer function unit 21 an inquiry result signal SG19 indicating that the user apparatus UA is newly installed. In this case, the MAC address advertisement reception function unit 17 also transmits to the address database 15 a MAC address advertisement information notification signal SG11 indicating the content of the received MAC address advertisement information. Thereby, the communication device CA can perform MAC address learning for the user device UA newly installed in the other communication device CA.

The header addition function unit 18 reads the header information of the communication device CA corresponding to the destination MAC address of the user data frame transmitted from the MAC address identification function unit 20 from the address database 15 as described in the first embodiment. . Then, the header adding function unit 18 can add a header to the user data frame based on the read header information and transfer it to the WAN port 12 .

(motion)
Next, operation of the communication device CA according to the third embodiment will be described.
FIG. 9 is a flowchart showing an example of the operation of the communication device CA when the communication device CA according to the third embodiment is the MAC address inquiry source. Also, FIG. 10 is a flowchart showing an example of the operation of the communication device CA when the communication device CA according to the third embodiment is the MAC address inquiry destination.

As shown in FIG. 9, the processor 1 of the communication device CA serving as the inquiry source functions as the MAC address identification function unit 20, and through the access port 11 in the first communication interface 4, the user data frame from the user device UA is processed. is received (step S41). When determining that the user data frame has not been received (NO in step S41), the processor 1 repeats the processing operation of step S41.

When determining that the user data frame has been received (YES in step S41), the processor 1 determines whether or not the destination MAC address of the user data frame has been learned in the address database 15 (step S42). .

If it is determined that learning has been completed (YES in step S42), the processor 1 reads the header information corresponding to the destination MAC address from the address database 15 (step S43). The processor 1 adds this read header information to the user data frame (step S44). Then, the processor 1 unicasts the user data frame to which this header information is attached from the WAN port 12 of the second communication interface 5, thereby transmitting it to the communication device CA corresponding to the destination user device UA ( step S45). After that, the processor 1 shifts to the processing operation of step S41.

Further, when it is determined in step S42 that the destination MAC address of the user data frame has not been learned (NO in step S42), the processor 1 functions as the buffer function unit 21 and stores the received user data frame as , is buffered in a temporary storage area provided in the data memory 3 (step S46).

Then, the processor 1 functions as the MAC address advertisement reception function unit 17 and advertises the MAC address of the user apparatus UA newly installed in another communication apparatus CA from the WAN port 12 in the second communication interface 5. to the other communication device CA (step S47).

The processor 1 also functions as the timer function unit 19 and starts a timer count for measuring a predetermined waiting time (step S48).

After that, the processor 1 functions as the MAC address advertisement reception function unit 17 and determines whether or not the new MAC address advertised by the other communication device CA is received from the WAN port 12 in the second communication interface 5 ( step S49). If it is determined that the advertised new MAC address has not been received (NO in step S49), the processor 1 functions as the timer function unit 19 and the buffer function unit 21 to determine whether the timer count has ended. , it is determined whether or not a predetermined waiting time has been measured (step S50). When determining that the timer count has not ended (NO in step S50), the processor 1 proceeds to the processing operation of step S49.

When determining that the timer count has ended (YES in step S50), the processor 1 functions as the discard function unit 22 and discards the buffered user data frame (step S51). Then, the processor 1 shifts to the processing operation of step S41.

As shown in FIG. 10, the processor 1 of the other communication device CA serving as an inquiry destination functions as a MAC address acquisition function unit 14, and uses the WAN port 12 of the second communication interface 5 to obtain a communication device serving as an inquiry source. It is determined whether or not a MAC address advertisement request has been received from the CA (step S61). When determining that the MAC address advertisement request has not been received (NO in step S61), the processor 1 repeats the processing operation of step S61.

On the other hand, if it is determined that a MAC address advertisement request has been received (YES in step S61), the processor 1, as in the second embodiment, receives data from the access port 11 of the first communication interface 4 by polling. , a MAC address reply request is transmitted (step S12). Then, the processor 1 shifts to the processing operation of step S13 and waits for receiving a reply from the newly installed user device UA.

After that, when determining that a response has been received from the new user apparatus UA (YES in step S13), the processor 1 stores the received MAC address of the new user apparatus UA in the address database 15 (step S14). The processor 1 then functions as the MAC address advertising function unit 16 to read the MAC address from the address database 15 (step S15), and transfer the read MAC address from the WAN port 12 of the second communication interface 5 to the network NW. Advertise on the top (step S16). After that, the processor 1 shifts to the processing operation of step S61.

When the processor 1 of the communication device CA serving as the inquiry source executes the processing operation as the MAC address advertisement reception function unit 17 and determines in step S49 that the advertised new MAC address has been received (in step S49 YES), it is determined whether or not the received new MAC address is the inquired MAC address (step S52). Then, if it is determined that the received MAC address is not the inquired MAC address (NO in step S52), the processor 1 proceeds to the processing operation of step S49, and the new MAC address advertised by another communication device CA. will wait to receive the

On the other hand, when determining that the received MAC address is the inquired MAC address (YES in step S52), the processor 1 pairs the received MAC address of the new user device UA with the device ID of the communication device CA. and store it in the address database 15 (step S53). Then, the processor 1 functions as the buffer function unit 21 and the header addition function unit 18, reads out the buffered user data frame (step S54), proceeds to the processing operation of step S43, and obtains the destination MAC address corresponding to the destination MAC address. The header information to be used is read out from the address database 15 .

If the communication device CA to which the inquiry is made does not receive a response from the newly installed user device UA even after the predetermined standby time has elapsed in step S13, that is, if the newly installed user device UA does not exist, reply information to that effect may be transmitted to the communication device CA that is the source of the inquiry.

In the third embodiment as described above, for example, in the communication system as shown in FIG. When a user data frame is received, it is determined whether or not the destination MAC address of the received user data frame has been learned. Upon recognizing that the first communication device CA1 has not yet learned the data frame, the first communication device CA1 buffers the user data frame, and then sends a new message to the second and third communication devices CA2 and CA3, which are other communication devices. Query MAC address. When receiving the inquiry, the second and third communication apparatuses CA2 and CA3 transmit a response request to the user apparatus UA by polling.

For example, when the second communication device CA2 acquires the MAC address from the response from the newly installed fourth user device UA4, the fact that there is a new installation and the MAC address are sent to the first and third communication devices, which are other communication devices. Advertise to devices CA1 and CA3. Thereby, not only the first communication device CA1 but also the third communication device CA3 can perform MAC address learning.

Also, since the third communication device CA3 does not reply because there is no newly installed user device UA, it replies that the first communication device 1 is not newly installed. It should be noted that such a reply indicating that there is no new installation is not necessarily required. Since the timeout function is provided in the first communication device CA1, the first communication device CA1 can determine that there is no new installation since there is no response from the third communication device CA3 within a specified period.

As described above, in the communication device CA according to the third embodiment, the MAC address acquisition function unit 14 receives a request for acquiring the MAC address of the newly connected user device UA, which is transmitted via the network NW. receives the MAC address advertisement request signal SG23, and acquires the MAC address of the newly connected user apparatus UA. In this way, the MAC address acquisition function unit 14 sends a MAC address acquisition request to the user device UA via the access port 11 upon receipt of a MAC address advertisement request from the communication device CA serving as an inquiry source, It is possible to acquire a MAC address and advertise the MAC address to other communication devices CA via the network NW. Therefore, the communication device CA that is the source of the inquiry can learn the MAC address and transfer the buffered user data frame. Therefore, the communication apparatus CA, which is the inquiry source, can learn the MAC address of the newly installed user apparatus UA at the time when the MAC address is required, that is, at an appropriate time.

That is, in the communication system according to the present embodiment, when the communication device CA serving as a transmitting device receives user data to be transmitted to the destination user device UA from the transmitting source user device UA via the access port 11, , a MAC address identification function unit 20 that identifies whether the MAC address of the destination user device UA has been learned, and when the MAC address identification function unit 20 identifies that the MAC address has not been learned, the network NW as a request function unit that transmits a MAC address advertisement information signal SG10 as a request to acquire the MAC address of the user device UA newly connected to the access port 11 of the communication device CA to the communication device CA serving as a receiving device via and a MAC address advertisement reception function unit 17 . Further, the communication device CA serving as the receiving device receives the MAC address advertisement request signal SG23 as a request to acquire the MAC address of the user device UA newly connected via the network NW. A MAC address acquisition function unit 14 as an acquisition function unit that checks whether or not there is a new connection to the user device UA of the new connection and acquires the MAC address from the newly connected user device UA, and transmits the acquired MAC address via the network NW and a MAC address advertisement function unit 16 as an advertisement function unit that advertises to the communication device CA serving as a transmission device. In this way, when the communication device CA serving as a transmitting device receives a user data frame having an unlearned MAC address as the destination from the user device UA, it inquires of the other communication device CA about the MAC address. A MAC address advertisement request is transmitted to the communication device CA. Triggered by the reception of the MAC address advertisement request from the communication device CA serving as the transmitting device, the MAC address acquisition function unit 14 of the communication device CA acting as the receiving device transmits the MAC address acquisition request to the user via the access port 11 . Send to the device UA and acquire the MAC address. Then, the MAC address advertising function unit 16 advertises the MAC address from the WAN port 12 to other communication devices CA via the network NW. As a result, the communication device CA, which is the transmitting device, can perform MAC address learning and transfer the buffered user data. Therefore, the communication apparatus CA, which is a transmitting apparatus, can learn the MAC address of the newly installed user apparatus UA at the time when the MAC address is required, that is, at an appropriate time.

[Fourth Embodiment]
Next, a fourth embodiment of the invention will be described. In the description of the fourth embodiment, the same reference numerals as those used in the description of the third embodiment are assigned to the same configurations and processing operations as those of the third embodiment, and the description thereof will be omitted. shall be

(Constitution)
FIG. 11 is a block diagram showing an example of the configuration of a communication device CA according to the fourth embodiment of the invention. The communication apparatus CA according to the present embodiment has the same configuration as that of the third embodiment, but the MAC address advertisement reception function unit 17 receives the MAC address advertisement request signal SG24 with MAC address notification instead of the MAC address advertisement request signal SG22. Send to WAN port 12 . As described above, in this embodiment, the communication device CA, which is the source of the inquiry, designates the MAC address to be advertised when requesting the advertisement of the new MAC address.

Therefore, the signal transmitted from the WAN port 12 to the MAC address acquisition function unit 14 is also the MAC address advertisement request signal SG25 with MAC address notification instead of the MAC address advertisement request signal SG23. Then, the MAC address acquisition function unit 14 transmits the MAC address notified by the MAC address advertisement request signal SG25 with MAC address notification to the MAC address advertisement function unit 16 as the MAC address notification signal SG26.

(motion)
Next, the operation of the communication device CA according to the fourth embodiment will be explained.
The operation of the communication device CA, which is the source of the inquiry, is the same as in FIG. It is the same as described with reference to the flow chart.

FIG. 12 is a flowchart showing an example of the operation of the communication device CA when the communication device CA according to the fourth embodiment is the MAC address inquiry destination. The processor 1 of the communication device CA serving as the inquiry destination functions as the MAC address acquisition function unit 14 and obtains the MAC address with MAC address notification from the communication device CA serving as the inquiry source through the WAN port 12 in the second communication interface 5. It is determined whether or not an advertisement request has been received (step S71). When determining that the MAC address advertisement request with MAC address notification has not been received (NO in step S71), the processor 1 repeats the processing operation of step S71.

On the other hand, when determining that the MAC address advertisement request with MAC address notification has been received (YES in step S71), the processor 1 accesses the access port 11 in the first communication interface 4 as in the second embodiment. Then, a MAC address reply request is transmitted by polling (step S12). Then, the processor 1 shifts to the processing operation of step S13 and waits for receiving a reply from the newly installed user device UA.

After that, when determining that a response has been received from the new user apparatus UA (YES in step S13), the processor 1 stores the received MAC address of the new user apparatus UA in the address database 15 (step S14). Then, the processor 1 functions as the MAC address advertisement function unit 16, reads out the MAC address from the address database 15 (step S15), and determines whether the MAC address matches the MAC address notified from the communication device CA that is the inquiry source. It is determined whether or not (step S72). If it is determined that it does not match the notified MAC address (NO in step S72), the processor 1 proceeds to the processing operation of step S71. At this time, the processor 1 may reply to the communication device CA, which is the source of the inquiry, that there is no new installation of the user device UA with the corresponding MAC address.

When determining that it matches the notified MAC address (YES in step S72), the processor 1 advertises the read MAC address on the network NW from the WAN port 12 of the second communication interface 5 (step S16). . After that, the processor 1 shifts to the processing operation of step S71.

As described above, in the communication device CA according to the fourth embodiment, the MAC address advertisement reception function unit 17 as the request function unit of the communication device CA serving as a transmission device receives the MAC address of the newly connected user device UA. MAC address advertisement request signal SG24 with MAC address notification as a request to acquire a specific MAC address, which is the destination of the user data in the MAC address acquisition function unit 14 of the communication device CA serving as a receiving device. In addition to the MAC address acquired from the user device UA newly connected with the reception of the MAC address advertisement request signal SG25 with address notification, the specific MAC address in the MAC address advertisement request signal SG25 with MAC address notification is MAC address notified. It is sent to the MAC address advertisement function unit 16 as a signal SG26, and the MAC address advertisement function unit 16 determines whether the MAC address acquired by the MAC address acquisition function unit 14 is a specific MAC address, and the acquired MAC address is specified. , the acquired MAC address is advertised. In this way, the MAC address acquisition function unit 14 of the communication device CA serving as a receiving device receives the MAC address notification from the communication device CA serving as a transmission device, and the MAC address acquisition function unit 14 receives a reply from the user device UA. It is determined whether the MAC address matches the MAC address being queried, and if they match, the MAC address is advertised. As a result, the communication device CA, which is the transmitting device, can perform MAC address learning and transfer the buffered user data frames. Therefore, the communication device CA, which is the transmitting device, learns the MAC address of the user device UA newly installed in another communication device CA, which is the receiving device, at the time when the MAC address is required, that is, at an appropriate time. becomes possible.

Note that when the MAC address acquisition function unit 14 of the communication device CA serving as the receiving device transmits the MAC address reply request to the user device UA, it corresponds to the specific MAC address notified from the communication device CA serving as the inquiry source. It may be configured to request a reply only when This makes it possible to omit matching determination in the MAC address advertisement function unit 16 .

[Fifth embodiment]
Next, a fifth embodiment of the invention will be described.
FIG. 13 is a block diagram showing an example of configuration of a communication apparatus CA according to the fifth embodiment of the present invention. As shown in the figure, the communication device CA according to this embodiment is a combination of the communication devices according to the first to fourth embodiments.

In this way, by combining the above-described first to fourth embodiments, a newly installed device can be installed before the time when the MAC address is required and at the time when the MAC address is required, that is, at an appropriate time. MAC address learning can be performed for the user apparatus UA.

Although the first to fourth embodiments are combined here, it is of course possible to combine two or more of the first to fourth embodiments instead of combining all of them. is.

[Application example]
The communication apparatus CA according to the first to fifth embodiments described above can be applied to various communication systems. Some application examples are described below.

[EVPN]
FIG. 14 is a schematic diagram for explaining an EVPN communication system. The EVPN communication system includes a provider edge PE installed in a network NW, which is a network on the operator's side, and a customer edge CE installed in a customer-side network such as a LAN. In the example of FIG. 14, a first provider edge PE1 and a first customer edge CE1 installed at a first site, a second provider edge PE2 and a second customer edge CE2 installed at a second site, and a third and a third provider edge PE3 and a third customer edge CE3 located at the site of

For example, when the second provider edge PE2 at the second site receives a signal from the second customer edge CE2, it learns the MAC address, and learns the MAC address, the first provider edge PE1 and the third provider edge PE at other sites. Advertise the MAC/IP Route to the edge PE3 in the form of Route Type 2. Then, the first provider edge PE1 and the third provider edge PE3, which have received this MAC/IP Route, based on it, the second customer edge PE2 connected to the second provider edge PE2, which is a provider edge PE other than the own device. MAC address learning of CE2 is performed.

In such an EVPN communication system, if the MAC address has already been learned, Unicast communication is transferred only to the appropriate provider edge PE. For example, when the first provider edge PE1 of the first site receives a signal indicating that the destination MAC address is the second customer edge CE2 of the second site, the MAC address of the second customer edge CE2 has been learned. , the first provider edge PE1 knows that the second customer edge CE2 is connected under the second provider edge PE2 of the second site, so it transfers the signal to the second provider edge PE2. can do.

However, when the MAC address is not learned, the source provider edge PE cannot determine under which provider edge PE the destination customer edge CE is connected. to the provider edge PE of For example, when the first provider edge PE1 at the first base receives a signal indicating that the destination MAC address is the second customer edge CE2 at the second base, the MAC address of the second customer edge CE2 is set to the unlearned In this case, since it is not known that the second customer edge CE2 is connected under the second provider edge PE2 of the second base, all the provider edge PEs in the same domain, the second provider edge PE2 and the second The signal is transferred to the 3 provider edge PE3.

Therefore, in the EVPN communication system, when the frequency of data communication from the customer edge CE is low and there are many unlearned MAC addresses, there are problems such as frequent occurrence of unknown unicast communication and pressure on the bandwidth of the network NW.

By applying the configuration of the communication device CA according to any one of the first to fifth embodiments to each provider edge PE, it becomes possible to perform MAC address learning at an appropriate time, thus solving such a problem. can do.

[Uninterrupted Redundancy Switching]
FIG. 15 is a schematic diagram for explaining a hitless redundancy switching communication system. The uninterruptible redundancy switching communication system includes a first uninterruptible device UD1 as a transmitting device, a second uninterruptible device UD2 as a receiving device, and two relay paths provided between them. and a relay route RR1 and a second relay route RR2. The first relay route RR1 is part of the first relay network and the second relay route RR2 is part of the second relay network. A first user terminal UT1 for inputting a user data frame UF, which is a signal to be transmitted, to the first uninterruptible device UD1 is connected to the first uninterrupted device UD1, which is a transmitter. A user data frame UF comprises, for example, a header and a data payload. Also, a second user terminal UT2 to which a user data frame UF received from the second uninterruptible device UD2 is input is connected to the second uninterrupted device UD2 serving as a receiving device.

The first uninterruptible device UD1, which is a transmitting device, assigns a sequence number indicating the sequence to the input user data frame UF, duplicates it according to the number of relay routes RR, and sends it to each relay route RR. do. In FIG. 15, the numbers written in the rectangles representing the user data frames UF represent sequence numbers. The second uninterruptible device UD2, which is a receiving device, selects the user data frame UF to be output to the second user terminal UT2 according to the reception timing of the user data frame UF via each relay route RR. For example, the second uninterruptible device UD2 determines the first-arriving user data frame UF based on the sequence number assigned to each user data frame UF received via each relay route RR, and determines the first-arriving user data frame UF. Delete the sequence number from the user data frame UF and output it to the second user terminal UT2. The second uninterruptible device UD2 discards the later-arriving user data frame UF. The second uninterruptible device UD2 holds the sequence number of the user data frame UF to be processed next in the form of an expected number. When a user data frame UF with a number different from the expected number arrives, waiting until the user data frame UF with the expected number arrives realizes communication without jumping in the order of the user data frames UF.

FIG. 16 is a schematic diagram for explaining an uninterrupted redundant switching communication system that supports multiple bases. In the hitless redundancy switching communication system in this case, two hitless devices, that is, second hitless devices serving as receiving devices, are provided for the first hitless device UD1 serving as one transmitting device. It includes a device UD2 and a third uninterruptible device UD3. A network switch NWSW is arranged on each relay route RR. The network switch NWSW converts the user data frame UF addressed to the second user terminal UT2 and the user data frame UF addressed to the third user terminal UT3, which are sent from the first uninterruptible device UD1, which is a transmitter, to a MAC address of Ethernet. It is transferred only to the uninterruptible device UD connected to the corresponding user terminal UT by learning.

In such one-to-many communication, in the first uninterruptible device UD1, which is a transmitting device, for the user data frame UF addressed to the second user terminal UT2 and the third user terminal UT3, the same as in the case of one-to-one communication If a sequence number is assigned to each of the relay routes RR1 and RR2 without discriminating the destination, the following problem occurs. That is, in this case, the network switch NWSW of the network including the relay route RR recognizes the user data frame UF addressed to the second user terminal UT2 and the user data frame UF addressed to the third user terminal UT3 by learning the Ethernet MAC address. is transferred only to the uninterruptible device UD connected to the user terminal UT. At this time, discontinuity occurs in the sequence numbers. In uninterruptible devices UD2 and UD3, which are receiving devices, if there is a discontinuity in the sequence numbers of a series of received user data frames UF, after waiting for the reception of the user data frames UF with missing sequence numbers, The next user data frame UF is processed. Therefore, the transfer time of the user data frame UF increases.

Therefore, in inter-site communication, as shown in FIG. 16, user data frames UF are classified for each pair of uninterruptible devices UD on the transmission side and reception side, sequence numbers are assigned to each pair, and user data Frame UF selection needs to be done. A logical classification unit based on a pair of uninterrupted devices UD for transmission and reception is defined as a traffic flow.

A user data frame UF to be transmitted to the second user terminal UT2, which is the destination, and a user data frame UF to be transmitted to the third user terminal UT3, which is the destination, are mixed from the first user terminal UT1 which is the transmission source. , is input to the first uninterruptible device UD1. In FIG. 16, among the user data frames UF, the user data frame UF to the second user terminal UT2 is hatched so that the user data frame UF to the second user terminal UT2 and the user data frame UF to the third user terminal UT3 It is shown to be distinguished from the data frame UF.

The first uninterruptible device UD1, which is a transmitting device, assigns a sequence number indicating the sequence to the input user data frame UF, duplicates it according to the number of relay routes RR, and sends it to each relay route RR. do. At this time, the first uninterruptible device UD1 associates the pair of uninterrupted devices as one traffic flow and assigns a sequence number to each. That is, the first uninterruptible device UD1 assigns

sequence numbers

1, 2, . Sequence numbers of 1, 2, . . . Also, an identifier for identifying the traffic flow is assigned. In the example of FIG. 16, the first identifier ID1 is assigned to the pair of the first uninterruptible device UD1 and the second uninterruptible device UD2, and the second identifier ID1 is assigned to the pair of the first uninterruptible device UD1 and the third uninterrupted device UD3. An identifier ID2 is assigned to each. As an identifier for identifying a traffic flow, a pair of MAC addresses of the user terminal UT of the source and destination contained in the user data frame UF, a pair of device IDs of the uninterrupted device UD of the source and destination, etc. can be considered.

Based on the MAC address learning information, the network switch NWSW on each relay route RR transfers the user data frame UF addressed to the user terminal B out of the user data frames UF transmitted from the first uninterruptible device UD1 to the second The user data frame UF addressed to the user terminal C is transmitted to the relay path to the uninterruptible device UD2 and to the relay path to the third uninterrupted device UD3.

The second uninterruptible device UD2 serving as a receiving device classifies the user data frames UF received via each relay route RR according to the identifier into traffic flows, selects a user data frame UF for each traffic flow, Output to the second user terminal UT2. For example, the second uninterruptible device UD2 determines the first-arriving user data frame UF addressed to the second user terminal UT2 based on the identifier and sequence number assigned to each received user data frame UF, and determines the first-arriving user data frame UF. The identifier and sequence number are deleted from the received user data frame UF and output to the second user terminal UT2. The second uninterruptible device UD2 discards the later-arriving user data frame UF to which the same sequence number is assigned.

Similarly, the third uninterruptible device UD3, which is a receiving device, receives the user data frame UF via each relay route RR, deletes the sequence number from the first-arriving user data frame UF, and Output to UT3. The third uninterruptible device UD3 discards the later-arriving user data frame UF to which the same sequence number is assigned.

As a result, there are no jumps, discontinuities, or duplications in sequence numbers, and redundancy switching can be achieved without increasing delay or frame loss.

In such an uninterruptible redundancy switching communication system between multiple bases, the uninterruptible device UD, which is a transmitting device, determines the uninterruptible device UD, which is a receiving device, from the MAC address of the user terminal UT of the transmission destination. and classify the traffic flow. Therefore, it is necessary to associate the MAC address of the destination user terminal UT with the destination uninterruptible device UD for learning. By applying the configuration of the communication device CA according to the first or second embodiment to each uninterruptible device UD, it becomes possible to learn the MAC address before the MAC address is required. .

For example, by receiving the user data frame UF from the second user terminal UT2 at the second site, the second uninterruptible device UD2 sends the MAC/IP Route advertisement to the first and third sites at the first and third sites. 1 and the third uninterruptible devices UD1 and UD3. As a result, the first and third uninterruptible devices UD1 and UD3 can associate and learn the MAC addresses of the second uninterrupted device UD2 and the second user terminal UT2. Similarly, the third uninterruptible device UD3 at the third site receives the user data frame UF from the third user terminal UT3, and thereby performs the first and second uninterrupted operations at the first and second sites. Advertise the MAC/IP Route to the devices UD1 and UD2. As a result, the first and second uninterruptible devices UD1 and UD2 can associate and learn the MAC addresses of the third uninterrupted device UD3 and the third user terminal UT3. When the user data frame UF whose destination MAC address is the second user terminal UT2 and the user data frame UF whose destination MAC address is the third user terminal UT3 are received from the first user terminal UT1, the first uninterruptible device UD1 , classifies the traffic flow corresponding to each user data frame UF from the prior learning information. Then, an identifier and a sequence number are assigned to the user data frame UF and transferred for each pair of transmission/reception uninterrupted devices. As a result, it is possible to realize uninterrupted redundant switching that distinguishes each unit of uninterrupted equipment between multiple bases.

As described above, if MAC address learning is performed in advance, appropriate traffic flow identification can be performed. occurs. Specifically, when unlearned, the uninterrupted device UD cannot identify the correct traffic flow, and transfers the same traffic flow as BUM (Broadcast/Unknown unicast/Multicast) as Unknown Unicast communication. Then, when the MAC address of the destination user terminal UT is learned during communication, Unicast communication starts from that timing, and since the correct traffic flow is identified, discontinuity occurs in the sequence numbers. This causes an inappropriate increase in delay.

Therefore, by applying the configuration of the communication device CA according to any one of the third to fifth embodiments to each uninterruptible device UD, MAC address learning can be performed when the MAC address is required. is desirable.

FIG. 17 is a block diagram showing an example of the configuration of a communication device to be applied as a hitless device UD in a hitless redundancy switching communication system. Here, the communication device according to the fifth embodiment is taken as an example, but the configuration of the communication device according to another embodiment may be used.

The communication device CA, which is the uninterrupted device UD in this case, has a traffic flow database (referred to as a traffic flow DB in FIG. 17) 23 . The traffic flow database 23 stores traffic flow information indicating identifiers and already assigned sequence numbers for traffic flows in pairs of communication devices CA.

When a series of user data in which user data frames with different destinations are mixed is received from the access port 11, the header addition function unit 18 assigns the destination user terminal UT to the address database 15 for each user data frame. Makes a read request for header information including the MAC address. As a result, header information including the MAC address of the destination user terminal UT and the device ID of the communication device CA is notified from the address database 15 .

Based on the header information, the header addition function unit 18 also transmits a traffic flow information read request signal SG27 requesting the traffic flow database 23 to read the traffic flow information. In response to this, the traffic flow database 23 transmits the stored traffic flow information to the header addition function unit 18 as a traffic flow information notification signal SG28. The header addition function unit 18 classifies which traffic flow each user data frame corresponds to based on the traffic flow information indicated by the traffic flow information notification signal SG28.

If there is already a traffic flow by the corresponding communication device pair, the header adding function unit 18 adds to the user data frame the identifier used by the traffic flow and a new sequence number as a header. Further, if the traffic flow by the corresponding communication device pair still does not exist, the header adding function unit 18 adds an identifier indicating a new traffic flow and a new sequence number to the user data frame as a header. The header adding function unit 18 then transmits to the traffic flow database 23 a traffic flow notification signal SG29 indicating traffic flow information indicating the identifier added to the header and the new sequence number. The traffic flow database 23 stores traffic flow information based on this traffic flow notification signal SG29.

In addition, the header adding function unit 18 duplicates the user data frame with the header added according to the number of relay routes RR, transfers it to the WAN port 12, and transmits it.

As described above, in the first to fifth embodiments, the uninterruptible device UD, which is a communication device CA serving as a transmitting device, is connected via the access port 11 to the user terminal UT, which is a user device serving as a transmission source, Each includes a user terminal UT as a destination user device and an uninterruptible device UD as a plurality of communication devices CA serving as a plurality of receiving devices connected via an access port 11, and is a transmitting device. A momentary interruption device UD duplicates user data received from a source user terminal UT, and a receiving device connected to a destination user terminal UT, which is the destination of the user data, via relay routes RR different from each other. It can be applied to an uninterrupted redundancy switching communication system that transmits to the uninterrupted equipment UD. That is, upon receiving a request to acquire the MAC address of a user terminal UT newly connected to the access port 11, each uninterruptible device UD serving as a receiving device receives a request to acquire the MAC address of the newly connected user terminal UT. A MAC address acquisition function unit 14 as an acquisition function unit that acquires an address, and a MAC address advertisement function as an advertisement function unit that advertises the acquired MAC address to other uninterruptible devices UD via a plurality of relay routes RR. a portion 16; Further, the uninterruptible device UD serving as a transmitting device receives and learns MAC addresses advertised by each of the uninterrupted devices UD serving as a plurality of receiving devices, and a MAC address advertising function unit 16 serving as a learning function unit for learning. When a series of user data in which user data frames with different destinations are mixed is received from the database 15 and the user terminal UT of the transmission source, each user data frame is transferred to the user terminal UT of the transmission destination that is the destination contained in the user data frame. Based on the MAC address of and the learned MAC address, it is classified into one of the traffic flows indicating the pair of the uninterrupted device UD serving as a transmitting device and the uninterrupted device UD serving as a receiving device. a header adding function unit 18 for adding to each user data frame a header containing a sequence number to be added to each user data frame and an identifier for identifying a pair.

[Other embodiments]
In the above embodiment, the case where the communication system includes three communication devices CA has been described as an example, but the number of communication devices CA may of course be greater than that.

It goes without saying that the processing procedure shown in the flowchart is an example and is not limited to this.

Also, EVPN and uninterrupted redundancy switching have been described as application examples, but it is of course possible to apply other than that.

The method described in each embodiment can be executed by a computer (computer) as a communication program (software means), for example, a magnetic disk (floppy (registered trademark) disk, hard disk, etc.), an optical disk (CD-ROM, DVD, MO, etc.), semiconductor memory (ROM, RAM, flash memory, etc.), or the like, or can be transmitted and distributed via a communication medium. The programs stored on the medium also include a setting program for configuring software means (including not only execution programs but also tables and data structures) to be executed by the computer. A computer that realizes this apparatus reads a program recorded on a recording medium, and in some cases, builds software means by a setting program, and executes the above-described processes by controlling the operation by this software means. The term "recording medium" as used herein is not limited to those for distribution, and includes storage media such as magnetic disks, semiconductor memories, etc. provided in computers or devices connected via a network.

In short, the present invention is not limited to the above embodiments, and can be modified in various ways without departing from the gist of the invention at the implementation stage. Moreover, each embodiment may be implemented in combination as much as possible, and in that case, the combined effect can be obtained. Furthermore, the above-described embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

DESCRIPTION OF SYMBOLS 1... Processor 2... Program memory 3... Data memory 4... First communication interface 5... Second communication interface 6... Bus 11... Access port 12... WAN port 13... Link-up detection function unit 14... MAC address acquisition function unit 15... Address database 16... MAC address advertisement function part 17... MAC address advertisement reception function part 18... Header addition function part 19... Timer function part 20... MAC address identification function part 21... Buffer function part 22... Discard function part 23... Traffic Flow database CA, CA1, CA2, CA3... Communication device CE1, CE2, CE3... Customer edge NW... Network NWSW... Network switch PE1, PE2, PE3... Provider edge RR1, RR2... Relay path UA, UA1, UA2, UA3, UA4 ... User device UD1, UD2, UD3 ... Uninterrupted device UT1, UT2, UT3 ... User terminal

Claims

A communication device connected to a user device via an access port and transmitting user data from the user device to another user device connected to another communication device via a network,
an acquisition function unit that acquires the MAC address of the user device newly connected to the access port in response to a request to acquire the MAC address of the user device newly connected to the access port;
an advertisement function unit that advertises the MAC address acquired by the acquisition function unit to other communication devices;
A communication device comprising:
2. The communication device according to claim 1, further comprising: a link-up detection function unit that detects link-up of said access port and transmits said request to said acquisition function unit upon said link-up of said access port. .
The communication device according to claim 1 or 2, further comprising a timer function unit that measures time and sends said request to said acquisition function unit each time a certain period of time elapses.
The communication device according to any one of claims 1 to 3, wherein said acquisition function unit receives said request transmitted via said network and acquires said MAC address of said newly connected user device.
A communication system in which a transmitting device connected to a source user device via an access port and a receiving device connected to a destination user device via an access port communicate via a network,
The transmitting device
Identification for identifying whether or not the MAC address of the destination user device has been learned when user data to be transmitted to the destination user device is received from the source user device via the access port a functional part;
A request to the receiving device via the network to acquire the MAC address of the user device newly connected to the access port of the receiving device when the identification function unit has identified that the MAC address has not been learned. a request function that transmits a
with
The receiving device
an acquisition function unit that, triggered by the reception of the request via the network, checks whether or not there is a new connection to a user device under the access port, and acquires a MAC address from the newly connected user device;
an advertisement function unit that advertises the MAC address acquired by the acquisition function unit to the transmission device via the network;
A communication system comprising:
a transmitting device connected to a source user device via an access port; and a plurality of receiving devices respectively connected to the destination user device via an access port, wherein the transmitting device is connected to the source user device via an access port. A communication system for duplicating user data received from a user device and transmitting it to the receiving device connected to the destination user device, which is the destination of the user data, via relay paths different from each other,
Each of the plurality of receiving devices
an acquisition function unit that acquires the MAC address of the user device newly connected to the access port in response to a request to acquire the MAC address of the user device newly connected to the access port;
an advertising function unit that advertises the plurality of relay routes for the MAC address acquired by the acquisition function unit;
with
The transmitting device
a learning function unit that receives and learns the MAC address advertised by each of the plurality of receiving devices;
When a series of user data in which user data frames with different destinations are mixed is received from the user equipment of the transmission source, each user data frame is transferred to the MAC of the user equipment of the transmission destination which is the destination contained in the user data frame. Based on the address and the learned MAC address, the traffic flow is classified into one of the traffic flows indicating the pair of the transmitting device and the receiving device, and the sequence number given to each of the user data frames for each track flow and the a header addition function unit that adds a header including an identifier for identifying a pair to each of the user data frames;
A communication system comprising:
A communication method in a communication device connected to a user device via an access port and transmitting user data from the user device to another user device connected to another communication device via a network,
the communication device obtaining the MAC address of the newly connected user device in response to a request to obtain the MAC address of the user device newly connected to the access port;
the communication device advertising the obtained MAC address to another communication device;
A communication method comprising:
A processor functioning as each of the functional units of the communication device according to any one of claims 1 to 4, or as each of the functional units of the transmitting device or the receiving device in the communication system according to claim 5 or 6. A communication program that lets you